In solar thermal power plants, thermal energy can be acquired from solar radiation, for example by means of parabolic trough receivers or tower receivers. In such examples, the thermal energy is then transferred to a fluid which is thermally coupled to a steam circuit. The thermal energy, at that point in the form of high-temperature heat, can consequently be converted into electrical energy by means of the steam circuit.
The production of the electrical energy, however, is directly coupled to the solar radiation. According to the prior systems, to decouple the production of the electrical energy from the solar radiation, thermal heat storage units are integrated in the steam circuit of the solar thermal power plant. Depending on type and size, the thermal heat storage units are used to compensate for short-term (clouds) and/or medium-term (night) interruptions of the solar radiation. Typical systems employ concrete storage units, salt storage units, or high-pressure water storage units as thermal heat storage units.